Thread-guard.



S. B. WILSON.

THREAD GUARD.

APPLIOATION FILED MAY 14, 1906.

HATENTEI) FEB. 5, 1907.

resting uponthe SARA B. WILSON, OF BUFFALO, NEW YORK.

THREAD- i specification of Letters Patent.

GUARD.

Patented Feb. 5, 1907.

Application filed May 14,1906. Serial No. 316.622.

T0 ull/ whom it may (Oil-(117711.

Be it known that I, Sana B. \VrLsox, a citizen of the United States,residing at Buftale, in the county of Erie and State of New l York, haveinvented a new and useful 1111- provement in 'lhread-Guards, of whichthe following is a specification. l

This invention relates to the guards or protectors employed inconnection with the spools oi sewing-machines for preventing the threadfrom winding around the spool-holder i of the machine and binding orinterfering} with its tension.

The object of my invention is to provide an el'licient guard of thischaracter which can be cheaply produced.

1n the accompanying drawings, Figure 1 is a side elevation of the guardwith a spool of l thread mounted thereon. Fig. 2 is a sec tionalelevation thereo'l. Fig. 3 is a {ragl mentar vertical section of theguard, on an enlarged scale, in line 3, Fig. 6. Fig. 4 is a similarsection in line 4 4, Fig. 6. Fig. 5 is a l side elevation of the guardwith the spool omitted. Fig. 6 is an enlarged bottom plan 1 viewthereof. Fig. 7 is a horizontal section in line 7 7, Fig. 5.

Similar letters of reference indicatecorresponding parts throughout theseveral views. A indicates the arm ol the sewing-machine, having theusual flat boss (I, and B is the spool-holder or post rising from saidboss.

The improved guard comprises a base C, boss a, and a hollow or tubularpost'D, extending upwardly from the base and secured centrally thereto,the base and the post looselysurrounding the spoolholder so as to befree to rotate thereon. The spool of thread E is placed upon the postand rests upon the base 0, the post being provided with means forcompelling it to turn with the spool as the thread is unwound therefrom.In the preferred construction shown in the drawings the post isconstructed of steel and provided with a number of longitudinal slots f,forming intervening e astic webs or tongues if, which are bulged midwaybetween the r ends and bear against the wall of the opening in the spoolwith suliil grooved pulley cient pressure to ause the post, the base,and the spool to turn together. The ..slots f are preferably taperedtoward their ends, so that the spring-tongues are narrowest at theirmiddle. In order to obtain the necessary frictional contact between thespool and the post and also adapt the latter to spools withdiil'erent-sized openings, the diameter of the bulged portion of thepost is somewhat greater than the bore of the spool-opening, so

that the spring-tongues f are compressed more or less in passing thespool over the post and pressing it down upon the base C.- These tongueswhile clamping) the s 001 to the post permit the spool to e rea ilyapplied to and removed from the post.

The slots f terminate short of the upper and lower ends of the post, sothat only the bulged central portion of the latter is free to contractup'on pressing a spool over it. This construction tends to prevent thesprin tongues f from bearing against the spoo holder and causing ends ofthe tongues by their connection with the solid unslotted end portions ofthe post sti'llening the bulged portions of the tongues and resistingtheir inward deflection.

The base C preferably has a concave face or groove extending fromitsupper to its lower edge, giving it the appearance of a orsheave. Theupper and lower edges of the base are comparativelf i sharp, so that noshoulders or abrupt edges are formed between the same andthe bottom ofthe spool and the flat surface of the boss'a. By this construction incase the thread drops below the spool it cannot enter between the spooland the base or between the base and the boss a and wind around thespool-holder,

but is kept away trom the latter by the con cave base.- Should thethread coil around the base, it will not become bound, but will simplyunwind from it as it does from the spool, and owing to the concave formof the base the thread will naturally seek the deepest part of anytendency of the thread to work between the base and the spool or betweenthe lower edge of the base and the boss (1.

The hollow post may be secured to the base by any suitable means. In thepreferred construction shown in the drawings the sheave-like base isprovided with a hub h, in which the lower end of 'the post is snuglyfitted and in which it is confined against upward displacement byoutwardlyturned lips 'i, formed at the lower end of the )ost andoverlapping the lower side of said hub, as shown in Fig. 3. The post isheld against downward displacement on the base by lugs j, projectinginwardly from the hub into notches it, formed in the ower end of thepost, as shown in Figs. 4 and 6. These inbinding of the spool, the

the groove, thus counteracting 5 terlocking lugs and notches alsoprevent the post from turning on the base.

I claim as my invention- 1. A thread-guard comprising a base constructedto fit over a spoolholder, and a hollow post rising from the base andhaving longitudinal spring-tongues bulged between their ends to engagethe bore of a spool and joined to the post at their upper and lower endsbut terminating short of the ends of the posh whereby the ton 'ues areheld against inward and outward displacement at their ends and onlytheir bulged middle portions are permitted to contract and expand,substantially as set forth.

2. A thread-guard, comprising a base constructed to fit over a spool-holder, and a hollow post rising from the base and provided withlongitudinal slots terminating short of its upper and lower .ends,forming spring-tongues which are joined to thepost at both ends, thecentral portions of the tongues being bulged and adapted to engage thebore of a spool, substantially as set forth.

3. A thread-guard, comprising a base conturn with said struoted to fitover a spool-holder, and a hollow post rising from the base and providedwith longitudinal slots terminating short of its upper and lower ends,forming spring-tongues which are joined to the post at both ends, thetongues being tapered from their ends toward their middle and theirnarrow middleportions being bulged, substantially as set forth. I

4. A thread-guard, comprising a circular base constructed to turn uponaspool-holder and adapted to support a spool, said base having a concaveannular iace extending from its top to its bottom, forming unshoulderededges at the upper and lower edges thereof, a hollow spool post securedto the base, and means for compelling the spool to I my hand thisIOth-day of May,

